Locking device for trailer hitches



Feb. 10151948'w a WERNER DEWGi-E FR TRILER HITCHS me@ GG'.. 2., 1946 INVHV TOR.

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Patented Feb. 10, 1948 2,435,857 LOCKING DEVICE `FOR TRAILER HITCHES l Arthur C. Werner, Lodi, Calif., assignor to Lloyd 11. Lukens, Lodi, Calif.

Application October 2, 1946, Serial No. 700,772

Claims.

This invention relates to, and it is an object to provide, an improved locking device for trailer bitches of the type which include a ball engaged .in a socket and a holding dog unit adjustably 4 andreleasably maintaining the ball and socket against separation; the locking device normally preventing accidental unlocking of the holding dog unit and undesirable resultant separation of the ball and socket.

Vprises a circular internal .ratchet on ,the hand wheel, and a spring-urged slide mounted on said body part adjacent the circular ratchet and intersecting the same for radial sliding movement relative thereto; the slide carrying a xed pawl u normally cooperating with the ratchet to prevent the hand wheel from rotating in a direction to -loosen the holding dog unit, andthe pawl being Vreleasable by manual movement of the slide to shift said pawl clear of the ratchet.

A further object of the invention is to produce -a, simple and inexpensive device, and yet one which will be exceedingly effective for the pur- .pose for which it is designed.

l lThese objects are accomplished by means of such structure and relative arrangement of parts as will fully appear by a perusal of the folowing specification and claims.

In the drawings: Fig. 1 is a side elevation, partly in section, showf ing the locking device asincorporated in a ball and socket type trailer hitch; said device being shown in its-normal or locked position.

Fig.A 2 is a fragmentary sectional elevation of lthe locking device, as in Fig. 1, but shows such device in its unlocked position.

Fig. 3is a sectional plan on line 3--3 of Fig. 1

Fig. 4 is an outer end view of the slide and inn eluded pawl, detached.

Fig. 5 is a bottom plan view of the hand wheel `illustrating the circular internal ratchet.

Referring now more particularly to the characters of reference on the drawings, the invention is here shown as embodied in a ball and socket l'type trailer hitch which includes anelongated body I adapted for connection in a conventional manner with the tongue of a, trailer; the body I being formed at its forward end with a downwardly opening socket 2 for the reception, in matching relation, of a ball 3. The ball 3 is formed with a neck 4 adapted to be coupled to the towing vehicle.

The ball 3 is normally maintained in the socket 2 by means of a holding dog unit, indicated generally at 5, which unit includes a releasable dog 6 bearing against the ball 3 on one side of the latter, and said dog 6 is vertically adjustable into cooperative relation with said ball 3, to prevent its escape from the socket 2, by means of a vertical adjustment bolt 1.

The vertical adjustment bolt 1 is formed, at its upper end, with a, non-circular head 8, and thence extends downwardly through the top portion of the body I rearwardly of the socket 2, and passes through the dog E. A nut 9 is threaded on the bolt 1 and is disposed in non-turnable engagement relative to the dog 6. A compression spring I0 4 surrounds the bolt 1 between the dog 6 and the part of the body I through which said bolt projects.

Upon rotation of the bolt 1 in 4one direction or the other, the dog 6 is thus tightened or loosened relative to the ball 3.

A relatively small hand wheel II is disposed above and in engagement with the top of the body I and the bolt 1 p-asses axially through such hand wheel; the latter including a socket I2 in which the non-circular head 8 relatively non-rotatably seats. With this arrangement, rotation of the hand wheel II causes corresponding rotation of the bolt 1 to tighten or loosen the dog 6.

When the hand wheel II is set to a position l for proper tightening of the dog 6 relative to the ball 3, it is requisite that a locking device be provided for the hand Wheel II, in order that the hitch parts remain locked against separation when the hitch is in use.

The locking device, which is the essence of the present invention, comprises the following structural arrangement:

'The top of the body I directly beneath the hand wheel Il, is formed with an annular supporting shoulder I3, against which the hand Wheel I I bears at and adjacent its periphery.

Radially inwardly of these bearing portions the hand wheel II, is formed with a circular internal ratchet I4, the inside diameter of which is concentric to but substantially greater than the diameter of the bolt 1, whereby to leave clearance therebetween.

The annular supporting shoulder I3 is radially slotted, as at I5, and a fiat slide I6 extends through the slot I5 inwardly of the annular support I3. The slide I6 increases in width to form outwardly facing stop shoulders II which normally bear against the annular supporting shoulder I3. The inner end, and increased width portion, of the slide I6 is formed with an elongated opening I'8 through which the bolt 1 passes; said bolt normally being disposed in the inner end of said elongated opening.

The slide I6 is normally maintained in such position by means of a compression spring I9 engaged between the body I and a down-'turned lip 2U on the outer end of the slide I6; said spring being disposed substantially parallel to said slide.

A pawl 2I is fixed on and upstands from the slide I6 in position to normally engage against one of the teeth of the circular internal ratchet I4.

As shown in Fig, 4, the pawl 2| is formed with :an abutment in one direction and an inclined face in the other direction, and is positioned so that the ratchet If4 may run over said pawl, by riding up .said inclined face, when the hand wheel `II isturned in a direction to tighten the dog 6. However, the abutment of the pawl :2I normally prevents -rotation of the hand wheel in anopposite direction.

`When it 'is desired to turn the hand wheel in such opposite direction, i. e., for the purpose of unloosening the dog 6 and separation of the ball 3 from the socket 2, the slide I 6 is first pushed `radially inwardly by hand, against the compression of spring I9. This shifts the pawl 2| from its normal position in engagement with the circular internal ratchet I4, to a free position radially inwardly of such ratchet. Thereafter, with the slide I6 shifting radially inwardly, the hand wheel II maybe freely turned in a direction to unloosen .the dog 6.

From thefo-regoing description it will be readily .seen that there has been produced such a device as substantially fulfills the objects of the invention as set forth herein.

While this specification sets forth in `detail the present and preferred construction of the device, still in practice such deviations therefrom may be resorted to as do not form a departure from vthe spirit of the invention, as defined .by the appended claims.

Having thus described the invention, the following is claimed as new and useful and upon which Letters Patent are desired:

.1. A locking device vfor a trailer hitch which includes a hand Wheel turnably mounted on a body part and an adjustment bolt extending axially from the handwheel through the body part, said locking device comprising a circular internal ratchet on the hand wheel adjacent said body part, an annular supporting shoulder included in said body part concentric to the hand wheel axis, the hand wheel bearing against said annular shoulder and the Yinternal ratchet being exposed radially inwardly thereof, a slide extending through the annular shoulder for motion radially of and adjacent the ratchet but xed circumferentially .of vthe latter, and a holding pawl on theslidenormallyengaged with the ratchet but releasable therefrom upon radial shifting of the slide in an inward direction.

2. A locking device for a trailer hitch which includes a hand wheel turnably mounted on a body part and an adjustment bolt extending axially from the hand wheel through the body part, said locking device comprising a circular internal ratchet on the hand wheel adjacent said body part, an annular supporting shoulder included in said body part concentric to the hand wheel axis, the hand wheel bearing against said annular shoulder and the internal ratchet being exposed radially inwardly thereof, a slide extending through the annular shoulder for motion radially of and adjacent the ratchet `but fixed circumferentially of the latter, and a holding pawl on the slide normally engaged with the ratchet but releasable therefrom upon radial shifting of the slide in an inward direction; the slide including ,an elongated opening therein radially inwardly of the ratchet, and the bolt extending through said opening.

V3.7A `locking device for a trailer hitch which includes a hand wheel turnably mounted on a body part and an adjustment bolt extending axially from the hand wheel through the body part, said locking device comprising a circular internal ratchet on the hand wheel adjacent said body part, an annular supporting shoulder included in said body part concentric to the handy wheel axis, thehand wheel .bearing against said annular shoulder and the internal ratchet being exposed radially inwardly thereof, la slide extending through the annular shoulder for motion radially of and adjacent the ratchet :but fixed circumferentially of the latter, Vand a holding pawl on the slide normally engaged with the ratchet but releasable therefrom upon radial shifting of the slide vin an inward direction, there being a spring urging the slide radially outwardly, and va stop on the slide'limiting outward motion thereof.

4. A locking device for a trailer hitchwhich includes a hand wheel turnably mounted on .a body part and an adjustment 'bolt extendingaxially from the hand wheel through'the body part, said locking device comprising a circular internal ratchet on the hand wheel adjacent said'body part, an annular supporting shoulder included in said body part concentric to thehandwheel axis, the hand wheel bearing against said annular shoulder and the internal ratchetbeing exposed radially inwardlythereof, a slide extending through the annular shoulder for motion radially of and adjacent the ratchet but fixed circumferentially of the latter, yand a holding pawl on the slide normally engaged with the ratchet but releasable therefrom upon radial shifting of the slide in an inward direction, there being a spring urging the slide radially outwardly, and a stop on the slide limiting loutward motion thereof, said stop being a shoulder on the slide bearing against the annular shoulder which supports the hand wheel.

5. A locking device for a trailer hitch Which includes a hand wheel .turnably mountedon a body part with its under face in contact with such body part, and an adjustment bolt extending axially from the hand wheel and through the body part; said locking device comprising a socket formed in the under face .of the hand wheel, ratchets formed in the peripheral wallof 4the socket, a `slide Aprojecting radiallyof Vtloelaxis of the wheel and being movable radially between the body part and under face of the wheel and xed against circumferential movement relative to the wheel, and a holding pawl on the slide projecting into the socket and engageable with the ratchets.

ARTHUR C. WERNER.

REFERENCES CITED The following references are of record in the file of this patent:

Number Number UNITED STATES PATENTS Name Date Hover May 16, 1933 Draeger Feb. 6, 1940 Martin Dec. 9, 1941 Atwood Aug. 15, 1944 Goodwin Mar. 19, 1946 FOREIGN PATENTS Country Date Great Britain Jan. 28, 1937 

